1. Field of the Invention
The present invention relates to an apparatus for the production of nitrogen, of the type comprising means for cooling compressed air from which water and carbon dioxide have been removed, rising means for progressively loading this air with nitrogen, and a condenser which is adapted for cooling the upper portion of these rising means by vaporization of rich liquid in order to produce a reflux therein. It applies more particularly to the production of nitrogen of average purity, i.e. typically between about 90 and 99%.
2. Description of Prior Art
The production of nitrogen is presently carried out by means of air distillation columns. If very pure nitrogen is not needed, one way would be to reduce the number of plates of the distillation column, however the economical benefit is low. With respect to the production by non cryogenic means (selective adsorption, selective permeation), it requires a large number of modules mounted in parallel, which is often unacceptable.